the effects of calcitriol on improvement of insulin resistance, ovulation and comparison with metformin therapy in pcos patients: a randomized placebo- controlled clinical trial

background: polycystic ovary syndrome (pcos) is the most common endocrine disorder in females of reproductive age. insulin resistance is a frequent metabolic disturbance in pcos. vitamin d deficiency is a common problem. accumulating evidence suggests that vitamin d has a role on insulin sensitivity so may contribute to reduction of hyperandrogenemia. objective: the aim was to determine the effects of vitamin d treatment in metabolic components and ovulation evidence in pcos. materials and methods: fifty one untreated pcos patients were randomly divided into three groups and treated with calcitriol, metformin, or placebo. before and 3 months after treatment, ovulation evidence was assessed by ovarian trans abdominal sonography. plasma fasting glucose, insulin, homeostasis model assessment insulin resistance (homa-ir), 25-hydroxyvitamin d, parathyroid hormone and androgen levels were measured before and after treatment. a 75gr glucose test was performed before and after treatment and two set of results was compared. results: three patients did not continue this study. only 11 patient (22.9%) had sufficient vitamin d levels (>30 ng/ml). metformin caused a significant decrease in weight (p=0.027), insulin level (p=0.043), and insulin resistance (p=0.048). systolic blood pressure and pth significantly improved after calcitriol (p=0.029, p=0.009 respectively). an improvement in ovulation was detected after calcitriol and seven patients, without evidence of ovulation before treatment, illustrated ovulation after 3 months. difference with calcitriol in ovulation was significant versus other two methods (p=0.02). conclusion: calcitriol treatment in pcos may be prior to metformin in ovulation induction.